The present invention relates to a socket apparatus which supplies power source for a vehicle to an adapter such as a cigar lighter etc.
Such a kind of related power source socket apparatus is shown in FIGS. 6 and 7. As shown in FIGS. 6 and 7, a power source socket apparatus 1 is configured by a socket main body 2 for a cigar lighter and an adapter 3. The cigar lighter socket main body 2 is provided with an insertion hole 4. Power source side contact points 5a, 5b are provided at the bottom wall 4a and the inner peripheral wall 4b of the insertion hole 4, respectively. The pair of the power source side contact points 5a, 5b are supplied with a power source voltage from the vehicle power source through a power source line.
The adapter 3 is provided at the insertion hole 4 so as to be freely inserted therein and drawn therefrom. Load side contact points 6a, 6b are provided at the tip end surface 3a and the outer peripheral surface 3b of the adapter, respectively.
When the adapter 3 is inserted into the insertion hole 4 of the cigar lighter socket main body 2, the load side contact point 6a on the tip end surface 3a of the adapter 3 is made in contact with the power source side contact point 5a on the bottom wall 4a of the insertion hole 4 and also the load side contact point 6b on the outer peripheral surface 3b of the adapter 3 is made in contact with the power source side contact point 5b on the inner peripheral wall 4b of the insertion hole 4, whereby the vehicle power source is supplied to the adapter 3.
The power source for a current vehicle outputs a low voltage of 14 volts. Thus, arc discharge scarcely occurs even if the power source side contact points 5a, 5b are respectively made in contact with or separated from the load side contact points 6a, 6b in a state where the low voltage is applied. Therefore, the related power source socket apparatus 1 is not provided with a mechanism for preventing the arc discharge.
However, in recent years, a high-voltage vehicle with an output power of 42 volts has been developed on which a motor generator advantageous in the fuel cost of a vehicle is mounted. According to such a high-voltage vehicle, the power source voltage is three times as large as the current power source voltage (14 volts) for a vehicle, so that the provability where the arc discharge occurs at the time of inserting and drawing the adapter is also three times as large as that of the current power source for a vehicle. Therefore, a mechanism for preventing the arc discharge is required. Further, the contact points are very likely damaged by the arc discharge and so a mechanism for preventing the arc discharge is required.
It is therefore an object of the present invention to provide a socket apparatus, which can prevent occurrence of the arc discharge at the time of inserting and drawing an adapter thereby to improve safety and prevention of disaster property for a user and also can prevent the damage of contact points.
In order to achieve the above object, according to the present invention, there is provided a socket apparatus for supplying a power source comprising:
a cylindrical adapter having a front face and an outer peripheral face, including;
a guide portion, provided on the outer peripheral face;
a first contact portion, provided on the front face; and
a second contact, provided on the outer peripheral face, and
a socket body having a cylindrical insertion hole into which the adapter is inserted, including;
a first guide groove for guiding the guide portion, provided on an inner peripheral face of the insertion hole,
a third contact portion, provided on a bottom face of the insertion hole, and electrically connected to the first contact portion when the adapter is inserted into the insertion hole;
a fourth contact portion, provided on the inner peripheral face, and electrically connected to the second contact portion;
a second guide groove, provided on the inner peripheral face so that the adapter pivots while the guide portion engages the second guide groove; and
a fifth contact portion, provided on at least one of the inner peripheral face and the outer peripheral face so as to continuously contact at least one of the second contact portion and the fourth contact portion, and the fifth contact portion is lower than the at least the second contact portion and the fourth contact portion in electrical conductivity, and
wherein the fifth contact portion is disposed on an upstream side in a rotation path of the second contact portion during the adapter pivots.
Preferably, the fifth contact portion is provided on the inner peripheral face so as to continuously connect the fourth contact portion.
Preferably, the second contact portion is separated from the fourth contact portion in a state that the adapter is inserted into the insertion hole along the first guide groove.
Preferably, the second guide groove is communicated with the first guide groove at a lower portion of the first guide groove, and the second guide groove is extending in a circumferential direction of the insertion hole.
In the configurations, when the adapter is inserted into the insertion hole of the socket body and then the inserted adapter is rotated, each of the second contact portion provided on the outer peripheral face of the adapter is contacted with the corresponding fourth contact portion on the inner peripheral face of the socket body through the fifth contact portion and thereafter directly contacts with the corresponding fourth contact portion. In a state where the second contact portion is contacted with the corresponding fourth contact portion through the corresponding low electric conductivity fifth contact portion, a low current flows therebetween. Therefore, an occurrence of the arc discharge at the time of inserting and drawing an adapter is prevented, thereby safety and prevention of disaster property for a user are improved and the damage of contact points can be prevented. Also, a high current flows for the first time when the second contact portion is directly contacted with the corresponding fourth contact portion.